Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 1 Flygteknik Oktober 2010 ASSESSING THE WELDABILITY OF NICKEL BASED SUPERALLOYS Joel Andersson

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 2 Volvo Aero Components Hot Structural Parts Maximum Temperatures for Hot Structural Part Alloys of Interest: 718Plus: 700°C Waspaloy: 750 °C Alloy 718: 650°C Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 3 Flygteknik Oktober 2010 ”Back to the Future” Weld Assemblies Make it Light

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 4 Flygteknik Oktober 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 5 Welding Simulation at Volvo Aero Flygteknik Oktober 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 6 Process Material mechanisms Experience/Testing Expert/Modeling Generic Knowledge Process ? Generic Weld Cracking

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 7 Weldability? Flygteknik Oktober 2010 To describe a material’s ability to be readily fabricated, to perform in service, or both.

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 8 Material’s resistance to cracking during fabrication  Hot cracking –Cracks associated with the presence of liquid in the fusion and heat affected zone  Warm cracking –Occurs at elevated temperatures in the solid-state, i.e. no liquid is present  Cold cracking –Occurs at ”low” temperature and is usually related to embrittling species Flygteknik Oktober 2010 Weldability

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 9  Self-restraint test – i.e. Circle patch  Simulative tests –Involves tension or bending to simulate high restraint levels in welds.  Hot ductility tests –Measure the strength and ductility at elevated temperatures. Flygteknik Oktober 2010 Weldability Testing - Hot Cracking

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 10 Flygteknik Oktober 2010 Material Form Influence Weldability! Cast Wrought

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 11 Homogenization of Cast Material AS-CAST Time [hrs] Temperature [ ° C] μm

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 12  Chemistry? –Melting point depressant and eutectic forming elements, e.g Nb, C, Si… –Harderners, e.g. Al and Ti –Trace elements like B, P and S Flygteknik Oktober 2010 In Addition, Chemistry! Hot Cracking and Strain Age Cracking (Warm cracking)

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 13 Superalloy Chemistry  Chemistry – wrought  Niobium –Segregation  Result of segregation –Carbides –Laves eutectics Flygteknik 2010 Wt%

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide PlusWaspaloy Chalmers University of Technology DSC JMatPro Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 15 ”Bend tests” at Aalto University, Finland Transvarestraint ProvningVarestraint Provning Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 16 QUENCH SYSTEM TEST CHAMBER PROGRAMMING UNIT GLEEBLE CONTROLLING UNIT SAMPLE THERMOCOUPLES GRIPS QUENCH SYSTEM TEST CHAMBER Gleeble test at University of Manitoba, Canada Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 17 Flygteknik Oktober 2010 Hot Ductility

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 18 Weld trials at Volvo Aero

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 19 Aging Diagram ’Strain Age Cracking’ Temperature, º C Time, sec ’’  ’’ Heating Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 20 Ni 3 (Al,Ti) ’’ Weldability limit Strain Age Cracking Diagram Flygteknik 2010

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 21 Summary Flygteknik 2010 Manufacturing Repair

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 22  Welding metallurgy must be fully understood! –Integrated with welding simulation!  Weldability in general (metallurgical standpoint) –Eutectic forming elements  Hot ductility Hot Cracking  Ability to heal cracks –Hardeners such as Al and TiSAC Flygteknik Oktober 2010 Summary

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 23 Flygteknik Oktober 2010 Thank you!

Volvo Aero Corporation Proprietary Information. This information is subject to restrictions on first page. Joel Andersson Utg. 12 Slide 24 Flygteknik Oktober 2010